Mold-coating for apparatus for casting pig metal.



No. 709,672. Patented Sept. 23, I902.

J. M. HARTMAN. MOLD COATING FOR APPARATUS FOR CASTING PIG METAL.

(Application filed July 25, 1901.)

(No Model.)

INVENTOR.

lufi! at.

WITNESSES:

I of pig-metal molds (1.

UNITED STATES PATENT Curios.

JOHN M. HARTMAN, OF PHILADELPHIA, PENNSYLVANIA.

MOLD-COATING FOR APPARATUS FOR CASTING PIG METAL.

SEECIFICATION forming part of Letters Patent No. 709,672, datedSeptember 23, 1902.

Application filed July 25, 1901. Serial No. 69,6 54. (N0 model.)

To all whom it may concern.-

Be it known that 1, JOHN M. HARTMAN, a citizen of the UnitedStates,residing on Gowen avenue, Mount Airy, in the city and county ofPhiladelphia and State of Pennsylvania, have invented certain new anduseful Improvements in Mold-Coatings for Apparatus for Casting PigMetal, whereof the following is a specification, reference being had tothe accompanying drawing.

My invention concerns machinery-such, for example, as is shown inLetters Patent of the United States No. 629,903, granted to me underdate of August 1, 1899-whereby a series of molds are led continuouslybeneath the point where molten metal is fed into them and thereafter arecooled by wetting with water and inverted, so as to dump the pig thuscast. My invention relates to a coating for such molds, having for itsobject to prevent the pig which has been cast from fusing and stickingto the mold and also to prevent explosions in case when the mold returnsto the spout to be poured there is water adhering to it.

In operating any continuous casting-machine a difiicult problem ispresented in preventing the molten metal from fusing to the mold.Garbonaceous material in manyforms, either as a dry powder or as apaste, has been tried, but only with partial success. I have discoveredthat finely-powdered bituminous coal dusted over the interior surface ofthe mold satisfactorily overcomes the difliculty.

In order to illustrate the application of my invention, I have shown inthe accompanying drawing in diagrammatic section a series This issupposed to be an endless series; but only so much thereof is shown asrelates to my invention.

17 is a refractory nozzle, through which the molten metal is fed intothe molds as they pass beneath it.

c is the end of a water-trough, into which the molds pass soon afterbeing filled with water. Cl is the other end of this watertrough, fromwhich the molds emerge after the metal has been sufficiently cooled bywetting therein. At e the molds are inverted and drop the pigs whichthey contain, immediately righting themselves as they pass on. Thus farWhat I have described does not differ from the arrangement shown in myprevious Letters Patent, to which I have referred.

f is a convenient receptacle containing finely-divided bituminous coaland fitted at its lower end with an aperture or other means for feedingthis coal into the molds. As will be observed, the feeding of thepowdered hituminous coal into each mold takes place be fore the moldreaches the point I), where the metal is poured into it. This materialhas a tendency to adhere to the sides of the mold as it is poured intoit, although some of it slides down to the bottom, where it is mostneeded, because of the fact that the metal is poured into the mold alongits median line. As the metal rises in the mold it pushes part of thedust up against the sides. The molten metal excludes the air from thedust, which consequently is not consumed by the heat, but adheres to thesurface of the mold as a sooty coating so firmly that after the mold andpig have completed their circuit through the water and the pig has beendumped the coating can be rubbed oif by the naked hand. Thereafter thissooty coating adheres tenaciously to the mold, doubtless owing to theoil contained in the bituminous coal, and continues to form a sufiicientbarrier between the mold and the pig to prevent adhesion of the one tothe other. The receptacle fis fitted with a slide f or some otherconvenient means for regulating the flow of the coal-dust therefrom. Asthe process proceeds the feeding of the bituminous-coal dust iscontinued from time to time as needed.

It is further desirable in providing a moldcoating for casting machinesto provide against the contingency of adhesion of water to the mold whenit comes beneath the pouring-point in order to prevent resultingexplosion. Aftera machine has been in operation for some time the moldsbecome so hot that they dry off as soon as they leavethe water,preventing the contingency mentioned; but when the machine is firststarted the molds are cold, and consequently come beneath thepouring-point wet. In order to prevent explosions before starting themachine, I grease all of the molds with refuse oil--as, for example,spent oil from machinery-journals or the waste oil sold under the nameof refuse by refineries. This effectually prevents the explosion which Ihave spoken of. As a convenient means for accomplishing this I providean oil-receptacle g, fitted with asprinklingdevicegandaregulating-valveg This is situated just in advanceof the point where the molds enter the water-trough, and during thefirst rotation of the machine before the pouring of the metal commencesthe oil is sprinkled into the molds. Before the first molds into whichmetal has been poured come beneath the oil-receptacle g the supply ofoil is stopped. In place of the device which I have shown it issufficient to station at the same point a man with a mop and a bucket ofoil. I am not able to state positively the reason for the efficacy ofthe oil, for notwithstanding the oil coating there may be watercontained in the mold; but I believe it to be because the presence ofthe oil prevents adhesion of the water to the mold,so that when the ironis poured into it the water instead of being imprisoned below the ironis pushed ahead of and on top of it. Whatever the reason may be I havefound that it effectually prevents the explosions which otherwise wouldoccur. After greasing the molds I sprinkle on the coal-dust,as aboveexplained.

Having thus described my invention, I claim 1. In a pig-metal-castingapparatus, the

combination of a series of metal-molds; means for wetting the saidmolds; and a coating formed of powdered bituminous coal applied to theinterior of the molds, substantially as described.

2. In a pig-metal-casting apparatus, the combination ofa series ofmetal-molds; means for circulating the said molds successively beneaththe point where metal is poured and through a wetting apparatus; and acoating for the interior of said molds consisting of powdered bituminouscoal, applied prior to the passage of the mold beneath the point wheremetal is poured, substantially as described.

3. In a pig-metal-casting apparatus,the combination ofa series ofmetal-molds; means for circulating the said molds successively beneaththe point where metal is poured and through a water-cooling apparatus;and a coating for the interior of said molds consisting of refuse oilapplied prior to the entry of the molds into the water and a furthercoating consisting of powdered bituminous coal applied prior to thepassage of the mold beneath the point where metal is poured,substantially as described.

JOHN M. HARTMAN.

Witnesses:

JAMES H. BELL, O. BRADFORD FRALEY.

